The present invention relates to a self-supporting floor plate of flat construction for heatable raised floors made up of a layer of an aged, mineral material, for instance anhydrite, concrete or the like, with a metal wrapper, wherein an electric heating line is embedded in this layer of mineral material, and the heating line engages with the wrapper.
In the case of raised floor plates of the above type, of those which have a relatively low structural height of for instance only about 3 cm, embedding the electric heating line in a uniform plane in the mineral material before the mineral material ages and hardens is generally problematic, especially when this plane is to lie in the statically neutral zone of the raised floor plate.
In the case of a known raised floor plate of the aforementioned structural type (German Offenlegungschrift No. 33 30 778), the wrapper consists of a metal frame which is approximately the height of the plate, in which a metal grating is affixed in the inside. With this construction, the electric heating line can be fastened to the metal grating before the age-hardenable mineral material is filled into the metal frame and is compressed therein. Therefore, in this case, the wrapper in the form of a grating can be constructed at the same time as the holder for the heating line. However, if the raised floor plate has only one wrapper on the outside in the form of a flat, metal shell which is open at the top, such as for instance is known from German Patent No. 20 04 101, the problem which has already been mentioned, of embedding the heating line securely in a preferred plane in the cross section of the flat layer of mineral material in the shell-shaped wrapper, still occurs.